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9/28/2012

Night of September 15th and 16th 2012 Observing


     I got an email from Dennis at Dobstuff.  He is going to work on a kit for a scope and then my rebuild of the 14 is next! Exciting! Looks to be on schedule for I hope late October, or at best before new moon in November.  I'll be doing a full review here and actually am going to film putting the scope together and using it as a YouTube video.  It is very exciting to me and I am very excited about the new design.  

On the evening of September 15th, I managed to get out to a location I have out west of FR006 Site 1.  I was by myself this night and enjoyed the tranquility of the evening and solitary nature of observing.  It was a good night stable air of which we haven't had much and the smoke had significantly lessoned.  Seeing this night was Antoniadi I to II depending on the time.  I have not touched up my stars on the open cluster sketches, these are as raw as they can be.  I need to get some practice time in on rounding my stars with a white gel ink pen though.  Sorry it has taken me so long to post, but I have been swamped with teaching, school and I currently have influenza so I am recovering from that.  





M27 the Dumbbell Nebula practice sketch from my Wolf Creek Observation.





M27 the Dumbbell Nebula based on my Wolf Creek Observation.





NGC 6826 Planetary Nebula in Cygnus, the Blinking Planetary.  XT10, 9/13/12; 10:58pm MDT; 7mm Pentax XW; FR 006 Site 1; Viewed at 196x with an Orion Ultrablock filter.  This is a bright planetary near 16 Cygni.  The fliers were evident with averted vision. Outer shell was dim, with a bright inner region.







NGC 6520 & Barnard 86 in Sagittarius; 9/15/2012; 10:10pm MDT; near Vernon; Antoniadi I; 14mm Pentax XW; 20mm ES 68 degree;  Type 1 Paracorr; Stunning open cluster with dark nebula B86 next to it.  About 70 plus stars in the FOV.  Dark nebula is wrapping around the open cluster. Great view.







NGC 6568 Open Cluster in Sagittarius; 9/15/2012; 10:45pm MDT; XT10, 10mm & 14mm Pentax XW; 20mm ES 68 degree with Type I Paracorr; Antoniadi I;   A nice S forming open cluster of 70 plus stars.  Central area doesn't have a lot of stars.  Most stars estimated in the 12th to 13th magnitude range.




NGC 6629 Planetary Nebula in Sagittarius;  9/15/2012; 11:05pm MDT; Antoniadi I; XT10, 5mm, 7mm & 10mm Pentax XW, Type I Paracorr;  Central star visible here at 240x, in this faint planetary that is rather small in size.  Very high surface brightness and round with a crisp edge.






NGC 6755 Open Cluster in Aquila; 9/16/2012; 01:05am MDT;  XT10, 30mm ES 82 degree and 20mm ES 68 degree; Antoniadi II;  Conditions are deteriorating slightly.  About 28 or more stars from around mag. 11.5 or slight fainter.  Bright knot of stars are just east of the center. This was a fun open cluster to observe.





NGC 6760 Globular Cluster in Aquila; 9/16/2012; 01:55a.m. Antonidia II with XT10, 5mm Pentax XW;  near Vernon Utah;  Somewhat bright globular cluster about 6 degrees NNE of Aquilae.  Some stars, 15 to 20 were resolved but not many.  Pretty round globular brighter inner core region.







NGC 6907 Barred Spiral Galaxy in Copernicus; May 15th, 2012; 09:35pm MDT; Mag. 11.9; Antoniadi I; Vernon West; XT10, 7mm Pentax XW; Favorite sketch and object of the night. Averted vision showed the outer arms but no hint of NGC 6908.  Galaxy has a bright inner core and evident bar that is east to west.  Spiral structure evident as in the sketch.







Palomar 11, Globular Cluster in Aquila;  9/16/2012; Antoniadi II; XT10, 7mm Pentax XW; Vernon near, Antoniadi II; Faint globular cluster, no real brightening near the core. The globular is diffused with no stars resolved.  Nice challenge object but don't expect too much if you look at this one.






NGC 6583 Open Cluster in Sagittarius;  near Vernon, Utah; 9/15/2012; 10:40pm MDT; Antoniadi I; XT10 27mm Panoptic and 30mm ES 82 degree;  About 30 plus stars resolved in mag. 13 to 15, many more evident.  Elongated NNW to SSW and stars extend to the west.  Nice.






NGC 7332 and NGC 7339 Edge on Galaxies in Andromeda (I believe); near Vernon Utah; 9/15/2012; Antoniadi I; 11:35PM MDT; XT10, 7mm & 10mm Pentax XW;  NGC 7339 lays east to west and has some mottling evident, with some brighter areas near the core and a stellar core. NGC 7332 has a box like core region and is very bright with a stellar nucleus.  The arms extend farther out on NGC 7332 (it is on the right in the sketch above).  This is a revisit of this pair and part of the Herschel 400.







NGC 6709 Open Cluster in Aquila;  9/16/2012; 12:10am MDT; Antoniadi I to II; near Vernon Utah; XT10, 30mm ES 82 degree & 20mm ES 68 degree;  Well over 100 stars are evident in this open cluster with ranges of mag 10 to 13.  The open cluster appears as a slanted triangle and on the east side is a nice double at mag. 10.  Nice.







NGC 6781 Planetary Nebula in Aquila. v Mag 11.4; 9/16/2012; 12:40a.m.; near Vernon, Utah; Antoniadi I to II; XT10 7mm & 5mm Pentax XW;  There is a 13.5 mag star on the NE edge.  The rim of this planetary is brighter than the inner core region.  Roundish in shape, there is a hint of irregularity on the southern edge which is also brighter and gives the PN a crescent shape appearance on the rim.  


9/09/2012

Explore Scientific 30mm 82 Degree Eyepiece Review

I received my 30mm 82 degree Explore Scientific eyepiece recently, and last night I was able to use it and view through it via a couple of telescopes.  As the 14 is on its way to Palm Desert, I had taken my 10 inch dob out to the Pit n Pole location out in the West Desert of Utah.  With me was my friend Jeff Porter and two of his associates from work I believe and then my friend Mat and his friend.  Jeff had a XX12i set up, a XT10i set up and a wonderful refractor that he had.  Mat was letting his friend (Gavin I believe) use his ATM 8 inch scope which is a wonderful scope, and Mat was using his ATM 16 inch scope which is fantastic.

Prior to getting into the night and the review of the eyepiece, I thought I would share a few things about the eyepiece.  First, is the box.  The box is extremely large and there is a reason for that.  Here is an image of just the box.  That is a medium size Sharpie and a normal size orange to give you size comparisons on the box.



This next picture shows the lid of the box off, the top layer of foam removed and the eyepiece revealed.  Yes, this is a massively large eyepiece!





This next image will show you the viewing glass on the top with the eye cup curled down.  In speaking of the eye cup being down, I found with this eyepiece I could view with the eye cup down using my glasses, but the best views came with my glasses off.  Luckily, I don't need my glasses while looking through an eyepiece, I just need it to view the sky and the constellations.






Here you can see the height of the eyepiece when compared to a regular, medium point black Sharpie pen.  I assume that most who are here will know from other reviews that this eyepiece is both large and heavy. For weight I get this eyepiece at coming in around 3.02 pounds vs the 2.2 pounds on the Explore Scientific site.  






Now comes the one negative aspect of this eyepiece that I am disappointed in.  It started on CloudyNights at this thread. Then on the first night of using the eyepiece I was not able to put a Lumicon OIII 2 inch filter or an Orion Ultrablock NB 2 inch filter.  I sent this report in to Explore Scientific: 

"I tried the ES 30mm 82 degree eyepiece last night for the first time and both a Lumicon OIII 2 inch filter and an Orion Ultrablock NB 2 inch filter would not fully screw on to the threads at the bottom of the eyepiece.  Both filters easy went in on my Paracorr so I could use them, but I would think that for the money, and for an eyepiece that has a wonderful reputation in the past, that the filters would easily thread on.  I have no problem with the 20mm 68 degree ES I own nor on the 4.7 ES 82 degree eyepiece I tried (and have on order).  As you can see from that thread and from my personal experience, you do seem to have a quality control issue with this eyepiece right now on the  threads on the use of filters.  If you want, I'd be happy to film putting the two filters on and sending it to you. Just thought you would be interested in this." 

I then received this reply: 

"Jay,

I have seen the thread.  However, you are one of the 1st to bring this issue to our attention and like I said before, I have put filters on this exact eyepiece before with no problems.  There is a possibility the the threading in your eyepiece could be either dirty or have some type of damage to them.  Have you tried to unscrew the silver barrel and then screw it on backwards, meaning the collared end would then be on the bottom of the eyepiece?  Then you could try those threads as they shouldn't have the black paint on them (which could also be giving you issues."



As you can see in this image, my eyepiece as held by my son, Nathan, does not have any black paint on the bottom threads.  If you do not have a filter slide or wheel like my friend Mat does (Mat has his own ATM filter slide on his 16 inch) and you need to screw a 2 inch filter on, please be aware that some of the newer Explore Scientific 82 degree 30mm eyepieces do NOT, I repeat DO NOT thread several key 2 inch filters into their grooves.  IF you don't have a filter wheel and use a Paracorr Type I with the white lettering or a Type II Paracorr you can screw the filter into the Paracorr and that will serve you well. As I stated, based on the reputation of this eyepiece, the current $250.00 price tag, I would expect the threads to work. Since this has happen to me and to a couple of people on Cloudy Nights, the conclusion has to be made that some of this otherwise terrific eyepieces may have some flaws on the filter threads. 




Now for reports on the glass in the eyepiece.  I did not write down in order all of the objects we viewed that night, but here are some.  Mat used  the 30mm 82 degree in his 16 inch f5.6 dob and we observed many objects with it.  It picked up Messier 11 revealing the Wild Duck or Borg Cube with in its entire field of view, and it was a marvelous view. We examined Messier 17 the Swan or Omega and without a filter in place it was a grand view, but sliding the OIII filter in showed far more structure of the nebula than the without it.  The Orion Ultrablock really extended the nebula far behind the Swan.  Stars were crisp to the edge in Mat's scope.  Mat used it for M51, the Veil Nebula which showed tremendous views of the Veil. We also took in the Double Cluster, M31 and its two companions.  The Cocoon Nebula showed my favorite view of the night in Mat's 16 inch scope and it was easily seen.

In my 10 inch I looked at several other objects and some of those listed above. In my 10 inch F4.7 dob the entire Double Cluster fit beautifully, and M31 was also terrific, though it was higher up in the sky and thus showing the dark lanes.  NGC 457 was framed nicely as was M103.  There were other objects but that is enough to give a review of the eyepiece.

The Explore Scientific 30mm 82 degree eyepiece is a tremendous eyepiece! I waited too long to get one. It gives about 95% of the view of a Nagler 31mm at a much lower cost.  Stars on all objects were sharp to the edge, and I did not notice coma in Mat's 16 inch f5.6 dob or in my 10 inch dob with a Type I Paracorr. Nebula were bright as were galaxies and open clusters.  As a finder eyepiece it worked really well.  Seeing was average and transparency last night was poor and I did learn not to use it to go after fainter galaxies as they don't stick out.  They were able to be found, but a trained eye is needed. So here I go.

Astgmatism Correction: A (none seen).
Lateral Color Correction: A
Distoration: A  (none observed)
Field Curvature: A+ (none seen).
Lack of Ghosting: A
Construction: A
Field of View: A+
Eye Relief: A
Cost/Benefit Ratio: A
Filter Fit:  C
Overall Grade: A- to B+ (the filter issue is holding this eyepiece back).

Yes, this eyepiece is as wonderful as so man have stated.  It's a keeper for the cost though I'll have to keep it and transport it in the box as it won't fit in my eyepiece case!

9/07/2012

A Strut Dob?



This is a 13.1 inch F4.5 and is from the DobStuff Website and is located at this link. This is similar to what my new scope should look like except it will have a dew shield and a couple of other items on it including a triangle string system to ensure no collimation shift.



Long time no post I guess. I have been swamped with the return to work and my own return to my advanced educational pursuits.  As I have mentioned, a couple weeks ago I took possession of a 14 inch Zambuto mirror that after two sessions, looks to be outstanding (of course).  It is now boxed back up and with some components from my XX14i, is being shipped to Dennis Steele at DobStuff to make a new Strut style dobsonian reflector. I knew that at some point I would be looking for a new structure to hold this mirror, and I considered heavily about building one, but lacking some of the major equipment I decided to have the old XX14i rebuilt into something better. Now don't take me wrong, my XX14i has been a wonderful scope and has served me faithfully for over 2 1/2 years.  It was sad to pull the "guts" out of the scope yesterday as I packaged everything and sent it off to Dennis.

The question will arise to why and why Dobstuff? There is another company back east that I had really considered but the wait time would be next May or latter and I am unwilling to wait that long.  Another reason is Albert Highe's new book that is out at Wilhelm Bell that discusses light weight scopes and that, hits to the reason I went they way I did.  I am not getting younger though I am still young I feel in the hobby in terms of my age.  More importantly my bad low back at L5/S1 dreads lifting the XX14i's bottom tube into my Pathfinder as I load and unload and load and unload on every dark sky trip.  The base though broken into 2 parts at home, isn't that friendly either to lifting.  The new scope will be much lighter and easier to transport. I had reached the point where lifting the bottom tube of the XX14i just made me dread thinking about observing. When your scope is getting you to question whether to go because of weight, its time to change some things in my opinion.

A strut? A STRUT? I've heard that from several people. I had considered Dennis' truss-hybrid design but after talking with Dennis on the phone, I felt more comfortable with the strut design.  The scope will be the 14 inch F4.62 mirror that I have at 1.4 inches thickness.  With that F ratio the notion of instability in the tubes is lessen because of the shorter length of the tube and I am adding a string design to make the scope more stable so that no variation occurs from horizontal to zenith in terms of movement of the scope so that collimation will hold. Dennis has a good explanation at his site located at this link. Jon Issacs over at CloudyNights owns a 16 inch strut from Dennis and he found the solution to his collimation shift using strings also.  The result is no collimation shift. For fun, here is a link to a 4 strut string telescope with some interesting features that is featured on Dennis' links.

Another concern is what about that fine Zambuto mirror? I observe in dusty, desert conditions and its easy for a small pebble to get thrown up.  Well, a dew shield for the primary put into place as seen in this link will protect the primary from dew, dust and small pebbles.  The advantage is the rapid cool down on the wonderful mirror and thus allowing better views in a quicker time which will maximize viewing times.  There are always trade offs in a scope design and I guess the main thing is to decide what trade offs are important enough not to compromise on, what one is willing to compromise on and how to minimize the impact overall on those items.

I have a dew heater for the secondary that will be installed and ready to go so that will ensure my secondary, especially in the fall and in the winter doesn't dew up.  I also have heard concerns about a shroud to help keep the dust out and to minimize stray light and I am sure I can make a shroud or purchase one from Shrouds by Heather (link) but this is one I believe I want to make myself. Keeping it out of the light path will be very important but I think that can be done either with black, rubber bungee cords, as shared over at CloudyNights: "On my 16" Lightbridge, I use 6 bungees stretched between the upper and lower tube assemblies to keep my shroud out of the light path. I use the black rubber type. I installed 6 hooks in UTA and 3 in the lower. I removed the S hooks from both ends of 3 straps and one end of other 3 straps. I slip the bungee ends over the hooks on the UTA, the three straps without S hooks on lower end are attached to hooks while the three with the S hooks are hooked to lower tube assembly truss securing knobs. I used to have a metal hoop to hold shroud out of light path but I find the bungee method works better."
As mentioned, I may use  two embroidery hoops position over the struts to keep the shroud out of the light path. We'll see on this after the scope is finished and I have it.  One thing is for sure, a scope is always a project.

So, what I am giving up by doing this? First, some money of course.  Next, in terms of the telescope I am losing the intelliscope feature.  Not a huge loss for me as I have only used it twice in the last year and those were at public star parties at our local library where there really are not any guide stars to find things at.  The rest of the time I star hop.  If I want to spend some more money then I could get the Sky Commander and the stalk with it.  The pro to this is that it can increase productivity since it takes you to an object instead of star hopping to it.  In the summer, when I may only have 3 to 4 hours to observe in good darkness, that can be a critical factor. However, I love to star hop, am extremely proficient at it and hunting down an object is part of the fun for me.  I don't do a lot of outreach so I think this may be something I opt out of.  One last pro though is that the scope becomes easier to sell if I ever choose that option if Sky Commander is on it.

Finderscope. Right now I think I am ready to not put both the Telrad and the 9x50 finderscope on the scope. I may change my mind on this as I have always enjoyed having a finder scope. Okay, the dovetail goes as I want the option of being able to put the finderscope on or not.  It will carry my Telrad and I have to state, dental floss made removing the base extremely easy. I am also have a Moonlight dual speed focuser installed on this new dob.  Color, I was thinking red, but I just like the notion of a black focuser on my scope.  It will fit with its new name, "Angel of the Night."  Hmmm . . . perhaps I birch should be stained black? No, it will be natural color as I like that the best.

Will this be a perfect scope? No, and I'll admit that upfront because I don't believe there is a perfect scope. I think we continue to play, and modify a scope for a long time seeking to improve its performance.  Will it be a scope that will last me for a LONG time? Yes. I like the 14 inch to 15 inch range, its the maximum size I want to use and going this route will make it lighter to transport.  Dennis offers a great product at a wonderful cost with premium results from what I have been told by a couple of people who own his product.  I'll be posting his images he sends to me of the build and of course, I'll post up when I get updates from Dennis as he builds it and as I receive the finished product from him. I intend to video tape the assembly so others can see how this works and give a review of the finished product after I have had it out under the dark skies of Utah's West Desert.  In the end I'm excited about this and will look forward to new scope as we move forward.  Comments are always welcomed.

My scope will be a little shorter than the measurements I give here since these are for a 14 inch F5 Hubble Mirror but the weights should be pretty close so I'll share them here.  They can be viewed at this link over at DobStuff. My eyepiece height should come in at 14x4.62=64.6 inches +/- 2 inches, or about what it is right now on the XX14i.


14" F5 with Hubble Optics mirror:
Weight of optical tube assembly w/mirror 44#
Weight of rocker box 25.5#
Weight of mirror box w/mirror 30#
Weight of mirror 19#
Height of eyepiece at zenith 71"
Rocker box size 21.75" x 20.75" x 13"
Length of struts 65"
Construction material Furniture grade Baltic birch 12-ply plywood